This invention relates to a system using storage media such as an IC card having an electronic circuit chip mounted therein or a magnetic recording card.
With the progress in miniaturization and thickness reduction of integrated circuit chips, a variety of new uses for such have been proposed. In Japanese Patent Laid-open No. Hei 3-38396, a technique is described for utilizing an electronic circuit chip for storing information by mounting the chip on a card along with an antenna device to allow information to be read from the chip by a non-contact reading technique. By storing information about the owner of such a card in a chip mounted on the card, the card can be used as an ID card. In addition, by storing information about an item to which such a card is attached, the card can be used as a tag of the commodity.
The amount of information that can be stored in an electronic circuit chip mounted on a card depends on the size of the card. The larger the amount of information required to be stored in the chip, the larger the size of the card. Because a large card is less portable, if portability is of importance, it is necessary to reduce the size of the card. A small card, however, allows only a small chip with a small amount of information. These relationships apply not only to a card using an electronic circuit chip, but also other storage media such as a magnetic recording card.
To allow information to be stored on a card having an electronic circuit chip, a RAM (Random Access Memory) or other writable memory must be included in the electronic circuit chip. In general, RAM is large and expensive in comparison with a ROM (Read-Only Memory). Thus, a card having an electronic circuit chip including RAM is less portable, and more expensive.
This invention provides a storage medium, such as a card with an electronic circuit chip mounted thereon or a magnetic recording card, which appears to a system as if the storage medium were a medium allowing information exceeding the storage capacity of the storage medium to be stored. It also provides a read-only storage medium.
The invention also provides a method of controlling information to be written into a storage medium used for storing ID information, a control apparatus for controlling the ID information stored in the storage medium and a terminal for reading the information from the storage medium and displaying it. In an operation to catalog information for the storage medium into the control apparatus, the ID information from the storage medium is read and transmitted to control apparatus which then catalogs the ID information and the information to be cataloged in the control apparatus. In an operation to examine information already cataloged in the control apparatus for the storage medium, the terminal reads the ID information from the storage medium and transmits it to the control apparatus to acquire the information already cataloged in the control apparatus. The control apparatus transmits the information already cataloged for the storage medium associated with the ID information to the terminal.
The storage medium typically comprises an integrated circuit chip in which ID information is stored in advance and an antenna for generating power by utilizing a received electromagnetic waves. The antenna allows information to be read from the electronic circuit chip and can also be used for transmitting the information. The electronic circuit chip and the antenna are mounted on a sheet, typically formed from paper or plastic. The terminal generates electromagnetic waves to read ID information from the storage medium without contacting the medium. Preferably, the information is encrypted, and the ID information read from the storage medium is transmitted to the control apparatus by using electromagnetic waves or a public network.
To store information, the terminal reads ID information from the storage medium, then transmits the ID information to the control apparatus with the information to be stored. The control apparatus catalogs the information received from the terminal into a memory in the control apparatus for the storage medium by associating the information with the ID information.
Because information to be cataloged for the storage medium is stored in a memory in the control apparatus and associated with ID information, the information to be cataloged for the storage medium can be handled as if it were possible to store the information into the storage medium, even if the amount of the information is greater than the storage capacity of the storage medium, or even if the storage medium is a read-only medium.
In addition to ID information, the storage medium can also be used for storing authentication information for the ID information. That information can be authenticated by the control apparatus with use of a key stored therein, in advance. Thus, it is possible to check whether ID information stored in the storage medium has been altered by using the authentication information stored in the storage medium along with the ID information. As a result, information security is improved.
If attribute information is stored in the storage medium in advance with ID information, the control apparatus can also be used for controlling ID information and information stored in the storage medium by associating them with the attribute information.
The terminal can be used for locally controlling some pieces of ID information and some pieces of cataloged information which are controlled by the control apparatus and associated with at least a piece of attribute information. For the terminal to examine information cataloged in the control apparatus, the terminal reads ID information and attribute information associated with the cataloged information from the storage medium, then checks whether the ID information is one of the pieces of ID information controlled by the terminal itself.
If the ID information associated with the attribute information is one of the pieces of ID information controlled by the terminal itself, the terminal immediately searches the pieces of ID information it controls for the ID information, and thus is capable of carrying out processing using a particular piece of cataloged information associated with the ID information. Thus, because it is no longer necessary to access the control apparatus, the operation to search the cataloged information can be performed locally in the terminal using high-speed processing. If the ID information associated with the attribute information is not one of the pieces of ID information controlled by the terminal itself, a piece of cataloged information and a piece of ID information associated with the attribute information are acquired from the control apparatus. Then, after the pieces of cataloged information and the pieces of ID information controlled by the terminal have been updated by using the piece of cataloged information and the piece of ID information acquired from the control apparatus, the terminal searches the pieces of ID information controlled by itself for the ID information read from the storage medium and processes it using cataloged information associated with the ID information found in the search.
The control apparatus can also be used for controlling ID information of the storage medium by associating the ID information with user ID information set by the user of the storage medium. In this case, to examine information cataloged in the control apparatus for the storage medium, the terminal reads ID information of the storage medium and transmits the ID information to the control apparatus. The control apparatus transmits cataloged information associated with the ID information received from the terminal and the user ID information. Because the user of the storage medium is allowed to provide user ID information serving as control information unique to the user itself to the storage medium, the user is capable of controlling the storage medium.